Safety alarm



y 1942; R. DALZELI I 2,283,354

SAFETY ALARM Filed Aug. 15, 1941 INVENTOR. R. D a 12 e ll Patented May 19, 1942 are SAFETY ALARM Richard Dalzell, Seattle, Washsassignor of onehalf toAd'olph 0. Stixru'd, Seattle, Wash.

Application August 15, .1941, Serial No. 407,079

Claims. (Cl. lid-68) as in metal shops, lumber yards, and logging operations in the woods, accidents and injuries sometimes occur to workmen, occasioned by the sudden breaking of some of. theparts, when at tempts are unintentionally made tolift greater loads than those for which the parts were de'- signed. H Y

It is therefore important to provideasignal to be operated, when excessive loads are connected to the hoisting cables or lifting parts, and

to be operated before the breaking point has been reached. In 'noisyshops and-places, and at distances in the woods, it has been found that an explosive sound is the most effective, no excessive and mental attention need be paid to the usual work of hoisting, because the sharp report of an explosion as from a revolver blank cartridge, will be heard over the other noises in the shops and at long distances in the woods, and give the necessary notice of danger; which may be then avoided by lessening the load, or providing stronger apparatus. I

It is therefore among the objects of this invention to provide, means for exploding a blank cartridge when an excessive load has been attached to hoisting means and before thebreaking'point 'of the apparatus has been reached in lifting.

Particular objects are to provide a housing to be coupled into a hoisting cable, with a coil spring mounted in the housing upon which the stress of the load is borne, by means of a shank on a hook or .eye'extended through the spring,

and said shank to carry an arm extending from oneside to be moved downward as the spring is compressed with the load, and then to cause the firing of the cartridge, when the spring and arm have been depressed by.the load to near the breaking point, and before the breaking takes place. With these and other objects hereinafter shown, I have illustratively exemplified mjyinvention by the accompanying drawing, of which: Figure 1, shows an elevation of the assembled parts, with a hook member for attaching loads. Figure 2, shows the hook, with the housing and some other parts insefction. Figure 3 is a cross section view taken on. line 33. of Figure 2. Figure 4 is a cross section view taken on line 4: i of Figur 2. .-Figure 5is an enlarged detail view in section of the chamber for holding a cartridge, and a firing pin above the same. Figure 6 is an enlarged detail view of the firing pin, and latch for retaining the pin in set position, with a trig gerbar for dislodging the firing 'pin, taken on line 6-6 of Figure 7. Figure 71s a cross section view taken on line 1'I of Figure 6, showing the .top of the latch, and a shoulder thereon against which the lower tapered end of the trigger bar operates for withdrawing the latch from the firing pin, when the bar is depressed bya load on thehook. Figure 8' is a viewof an alternate form of a member for attaching a load, providing an eye instead of a hook. I

Like numerals on the different figures represent like parts. Numera1 l0 represents a hook member for attachment to, loads to be raised, and to be operated from the cable I l, on which power is applied. The hook is suspended from a housing l2, which in turn is provided with side shackles 13, connected by pivots M and i5 for pivotal operation with the cable. The housing is preferably divided into a support chamber l6, and a signal chamber IT. A flange 18 in the base of the chamber l6, sustains a relatively heavy coil load spring l9. The hook is provided .with a shank 20 which'is extended up through the spring and carries a thread 2| at the top, upon which a suitable nut 22 is looked over a ball race comprising bearing balls 23 and or-' 'dinary retaining plates 23' above'and below the balls. Beneath the ball race and upon the shank of the hook is disposed a pressure ring or washer plate 2 Lv The washer carries an integral arm 29 which is extended laterally, for creating a sound signal when the load on the hook has depressed the washer and spring to a predetermined point. These parts may be assembled down through an opening 25 in the housing which may be then closed by a dust cap 26. v A partition 21 between the chambers isprovided with a slot 28 through which the armis operated. Within the chamber l1 and spaced beneath'the arm, is an adjustable block member 3i provided with a barrel 32 in the lower portion thereof, of suitable diameter for receiving a blank cartridge 33 of, any standard form,with

cap 33" and rim 34. A groove 35 around the barrel is provided to receive the rim and support the cartrid e in suitable position. A doorway 46 through the wall of the block permits the insertion and removal of the cartridges. .A firing' pin 36 is slidably positioned in the upper portion of the barrel for exploding the cap and cartridge for the signal. A post 30 is extended above the pin point, provided with a flange 36' upon which is mounted a propulsion spring 31, the top of which is extended against the ceiling above.

In order to retain the spring 3'! in compressed condition for propelling the point 36, a latch spring 39 is connected as by a screw 40 to one side of the block, which carries at the top a latch or lip, 4|. This lip is normally pressed inward through a slot 42 and into the barrel and upon which the flange 36 and pin are then supported. The lower edge of the lip as at 43 and the upper edge of the flange 36 are preferably beveled to facilitate the setting of the pin and spring 31 above the latch in readiness for firing the cartridge. The pin may be so set up, and the spring 31 compressed by the operator using any rod entered from below, before the cartridge is placed.

when the coil spring has been compressed to a predetermined safety point, an explosion barrel adjustably mounted in the housing in spaced relation beneath the arm, means for supporting a cartridge in the barrel, a latch resiliently pressed into one side of the barrel, a firing pin for exploding the cartridge normally supported by the latch, a propulsion spring normally compressed by and above the firing pin in the upper portion A portion of the lip is narrowed to form a shoulder 44 as seen in Fig. 7, to provide a fulcrum for Withdrawing the latch from beneath the firing pin. Adjacent this shoulder is slidably positioned a tapered lower end 45 of a trigger bar 47. The body of the bar is slidably disposed upward through a socket 49 to a point slightly below the actuating arm 29. The tapered point is normally sustained above the latch by a light spring 48, which is compressed between a collar 5| on the bar, and the base of the socket. A cap plate 50, attached to block as by screw 52, prevents the collar and bar from being lost from the socket. The lower end of'the bar above the tapered point is slidably disposed through a hole in the block above the latch, and this hole is extended beneath as.49', to permit the lower and tapered point to be pressed downward by the arm for expelling the latch from beneath the firing pin.

The several parts are so adjusted, that-when a predetermined load on the hook has drawn down and compressed the load spring [9 to a point near the danger limit, that the arm will have also depressed the trigger bar till the latch is removed from the firing pin. Thereupon the spring 31 projects the pin 'down upon the cap, and explodes the cartridge. The cartridge being confined in the block barrel except at its lower end, creates a loud report, which is readily heard and distinguished from othersounds; After the discharge, the block may be removed by releasing the set screw 52, the empty shellremoved and a fresh cartridge replaced. The firing pin is pressed above the latch, and the block re placed, ready for any possibly future overloading of the hook; The parts being enclosed by the housing, permits the apparatus to be freely used and transported, without danger of exploding the cartridge, until an overload is attached to the hook.

In some cases it is preferable to replace the hook member by a closed link member or eye as 53 and 54, on a shank with thread 2| for the holding nut 22. By the use of such an eye, the apparatus maybe mounted' elsewhere, in the cable line. 7

Having described my invention, I claim as new:

1. A safety apparatus for sounding an alarm when a predetermined load has'been raised by a lifting cable, comprising a housing coupled in the cable, a coil spring mounted in the housing, a hook for connection with theload to be lifted,

a shank extended from the hook through the spring and supported thereby, an arm extended laterally from the shank for causing an alarm of the barrel, a trigger bolt slidably mounted between the latch and the arm and having a tapered lower point adjacent the latch adapted to release the latch from the firing pin and propulsion spring for exploding the cartridge, when the arm is lowered to a predetermined point by the load on the hook.

2. A housing supported by a hoisting cable, a member for attaching a load extended from the housing, a spring mounted in the housing and forming the sole supporting means for the attachment member, and being adapted to carry a predetermined load with safety before becoming compressed by an overload .tending to the breaking of the parts, an explosive cartridge adjustably disposed in the housing, said attachment'member provided with a shank extended to above the spring and having an arm at right angles therewith, a firing pin resiliently and slidably mounted above the cartridge, and means operated by the arm for projecting the firingpin upon the cartridge for firing the same when the spring has been compressed to the predetermined limit for safety.

3. A swinging housing for lifting weights, a load spring mounted in the housing, a lifting hook provided with a shank supported entirely by the load spring, an arm extended laterally from the shank for creating an alarm when the load on the hook has reached a predetermined limit, an explosive body mounted in the housing, a trigger bolt adjustably disposed beneath the arm,'and adapted to be depressed when the arm is depressed by the load, means ,operatively connected with the .bolt for firing the explosive when the load has depressed the arm to, a predetermined danger point. t

4. A suspension eye including a swinging support, a shank portion on the eye withinjthe support, a lifting spring in the support and forming the sole suspending means for the eye, said spring adapted; to sustain a predetermined load with safety before becoming compressed by an overload tending to the breakage of thep'arts, an explosive body mounted in the support to provide a sound signal when the spring has been compressed to near the limit of safety of the parts, an arm extended laterally from the shank, and means operated 'by the arm for firing the explosive, when the spring has been compressed to the limit of safety by the load.

5. A suspension hook including a swinging support for hoisting loads, the hook having a shank portion within the support, a spring in the support and forming the sole suspending means for the hook,said spring being adapted to support a predetermined load with safety before becoming compressed to a danger point by an overload tending to the breakage of the parts, and an explosive carried by the support and being automatically responsive toexplode by the yielding of the spring for an alarm when an overload is met.

RICHARD DALZELL. 

